Sterilizing apparatus

A sterilizing apparatus radiating light including ultraviolet rays onto a target object, comprising:

• a laser light source oscillating second wavelength light having a peak wavelength in a range of 400 nm or more and 460 nm or less;
• a light frequency converter receiving the second wavelength light oscillated from the laser light source, the light frequency converter converting a portion of the second wavelength light into first wavelength light having a peak wavelength in a range of 190 nm or more and 230 nm or less,
• the light frequency converter emitting the first wavelength light and the second wavelength light not being converted into the first wavelength light;
• and
• a light intensity reducer changing the ratio of the light intensity of the first wavelength light to the light intensity of the second wavelength light while the sterilizing apparatus is operated, wherein
• light intensity of the ultraviolet rays of a wavelength range of more than 230 nm and less than 400 nm radiated onto the target object is less than 3 mW/cm2,
• the ultraviolet rays of the wavelength range of more than 230 nm and less than 400 nm radiated onto the target object with less than 3 mW/cm2 of the light intensity suppresses harm to somatic cells, and
• the light intensity reducer reduces the second wavelength light by absorbing or reflecting a portion of the second wavelength light emitted from the light frequency converter, and, the light intensity reducer transmits, without reducing, the first wavelength light emitted from the light frequency converter.